Abstract
An interval-fuzzy chance-constrained integer programming (IFCIP) method is developed for contamination control of a fluid power system (FPS) under uncertainty. The model is derived by incorporating the techniques of fuzzy and chance-constrained programming within a general interval-optimization framework. It can tackle uncertainties presented as both fuzzy members and discrete intervals. The developed method is applied to a case of a one-year contamination control planning for FPS. Interval solutions associated different risk levels of constraint violation are obtained, which can be used for generating decision alternatives. Generally, willingness to take a higher risk of constraint violation will guarantee a lower system cost; a strong desire to acquire a lower risk will run into a higher system cost. Thus, the method provides not only decision variable solutions presented as stable intervals but also the associated risk levels in violating the system constraints.
Acknowledgements
This research was funded by Natural Science Foundations of China (50675074 and 50775081), National High-tech R&D (863) Program (2006AA09Z238), NCET of State Education Ministry (NCET-07-0330) and PHR (IHLB) 20090203.